Antipick lock



May 28, 1940- -s. BRAUNE 2,202,329

ANTIPICK LcK Filed July 1s, 193s 5201022 mww bodying a cylinderrotatably housing a key plug APatented May.v I* 1 940 AN'rlrl'ckLocK lSholom Braune, Fitchburg, Massf ,Application July 13, 1939, serial No.284,334` 'v 4s claims. y (01570-419)y This invention relates to lcertainnew and use` tul improvements-Vin-antipick lock.

The primary object `of they invention is to pyro-fl vide a key plugnormally restrained/ against ro- 3 tation Within a lock cylinder bymeans of tensioned co-acting driver pins and pin tumblers with thevdriver pins and rotatable key plug cooperatively constructed to prevent`unauthorized or surreptitious operation or picking of the lock intheabsence of the proper operating key therefor. f

A vfurther object of the invention'is-to provide apick-proof lockof theforegoing character emwithtensioned topdriver pins coacting with pintumblers tourestraingthe ykeylplug from rotation, vthe cylinderl and keyplug having registering holes therein for the mounting of the driverandpin tumblers, the side of the key plug through which the holes extendbeing longitudinally flattened or.'

milled to provide a'flat vsurface at each side-of the tumbler vpinholeand an over-hanging side shoulder for' interlocking engagement with amushroometype driver pin to prevent rotation 'of .Y the key plug to thereleasing position` of ythe lock bolt.Y i

l With the above and other'objects in view that ywill become apparent asthe nature yof* the inev vention is better' understood, the.same'consists 5G- inthe novel form, combination and arrangement of partshereinafter more fully described, shown in the accompanying drawing andclaimed. In the drawing: I

- Figure 1 is a longitudinal sectional View of a {pick-proof lockconstructed in accordance with the present invention, a key beingillustrated as positioned inv the key'plug and the tensionecly driverpins and. tumbler -pins forming a part of thelockr mechanismbeingpositioned to permit rotation of the key plug;

Figure 2 is a vertical cross-"sectionalv View of the lock structureshown in'Figure l, the key beingremoved, the key plug'being partlyrotated with arnush-room-type driver pin interlockingly engaged with theside shoulder orvflangeborder-'i ing a longitudinally milled portion onthe side of the-key plug; Y

@Figure 3 is Ian enlarged perspective view of the l key plugremovedfrom' the cylinder and illusl' trating' the milled side* of thevplug through which `the tumbler openings extend V`-and'illustrating al'c'ngituclinallyv extending overhanging flange at each side of the'milledfsurfac 1` Figure 4 is a topvplan view on a reduced'scale y ofanotherfform of keyplug havingtumbler pin openingsv and a milled surfacewith alongitudif nallysplit bearingr sleeve surrounding the 'plugWith'the split ends thereof terminating at oppoe site edges ofthe milledsurface; `and f Figure 5 lis a topplan View of another form ofV bore.therein for the rotatable-reception of a key plug I2. The forward end:of the key plug I2 is; provided Witha'n enlarged annular-flangel3cooperating withthe walls of a' recess formedfin. the front Wall Ill ofthe cylinder I0 to limit inf jecting beyondzthe inner end. of thecylinder I0y and rcarrying a substantially; rectangularblocky projectionI5 rfor the mountingjof alaterally di rected lockinggar'm or bolt-I6,thatfis movable overy the inner end of the cylinder I0 as will bereadilyunderstood from anv inspection of Figure 1, :with the lock-boltretained in position onpthe key plug I2 by means of screws'or the likepassed therethrough and enteringrthreaded openings I1 in .the inner endof the key plug I2.

ward movement of the key plug in the cylinder,4 the inner orrear end ofthe'key plug I2 pro-.A

' The key plug I2'has alongitudinally extendn ing key slot` lextendingcompletely through the same, the side walls of the key slot beingribbed,y

.and grooved ina conventional manner for the mating reception of theshank kI Soi an operating key for the lock and said key plug further hasa longitudinally extending seriesr of radially gli-. v

rected holes20 therein opening at oneside of ,thev

key plug, I2 and ycommunicating with the key` slot. I.4 Asshown inFigures 1 and v2,.tumbler pins 2ly of varying vlength for coaction withthe wards of the key I9, are mounted-.in the holesZ,

A longitudinally extending series of .radially disposed holes 22 isformed inthe cylinder IllftheA v open ends of the. holes 22communicating A.with

the bore inthe cylinder in whichthe key plug V'Iv2.

is mounted and said holes 22iare vspaced for registry with correspondingholesv 20 in the key plug I2 as shown in Figure 1. lTop driverfpins234.gif,` themushrooln-type are loosely mounted in the` holes 22 in4 thecylinder..l0, 'the driver .pinsnxZv being preferably of varying lengthsandeach inn-N cluding an annularly reduced neck 24 adjacent its innerend providing a disk head 25 at the lower terminal end of the pin 23.Each hole 22 houses a coil spring for forcing the top driver pins 23 indirections toward the key plug I2.

The top surface of the key plug I2 is longitudinally cut-away or milledas at 21 in line with the surface ends of the holes 20 as clearly shownin Figures 2 and 3, the milled surface 21 extending laterally of eachside of the holes 20 providing longitudinally extending grooves 28 andinwardly directed overhanging side flanges 29 at each longitudinal sideof the series of holes 20.

With the key shank I9 in the key slot I8 of the key plug I2, as shown inFigure 1, the tumbler pins 2| are raised to elevate the top driver pins23 against the tension of the springs 26 associated therewith forpositioning the contacting ends of the top driver pins and the tumblerpins in the plane of the bearing surface between the key plug I2 and thebore in the cylinder I0 and at which time the key plug I2 may be rotatedby the key shank I9 for the operation of the lock bolt I5. When the keyshank I9 is removed from the key plug I2, the springs 26 force the topdriver pins 23 and the tumbler pins 2l in a downward direction into theopenings 20 in the key plug I2. If an attempt is made to pick the lockby the surreptitious operation of the tumbler pins and driver pins inthe absence of the authorized key illustrated, upward movement of thetumbler pins 2l will elevate the top driver pin 23 against the tensionof the spring 26 with the head 25 upon the lower end of the top driverpin moved outwardly of the hole 20 and into the plane of the milledsurface 2l. A partial rotation of the key plug I2 causes the head 25 ofthe top driver pin 23 to ride upon the milled surface 2'I and beinterlockingly received in a side groove 28 with the adjacent flange 29l moving into the reduced shank of the top driver pin afforded by thereduced neck 24 and into the position shown in Figure 2 whereupon it isimpossible to further elevate the top driver pin 23 to place the sameupon the periphery of the key plug I2. There isno position of rest uponthe' milled surface 2l of the key plug I2 upon which all of the topdriver pins 23 could be p0- sitioned and accomplish subsequent rotationof the key plug for the lrelease of the lock bolt I6 because any slightmovement of a rotary character of the key plug I2 will vpositively forman interlocking connection between the ltop driver pins 23 and the keyplug so that it is impossible to pick the mechanism of the lock.

In the form ofthe invention illustrated in Figure 4, the key plug has atop longitudinally milled surface 2l with holes 20 opening at the milledsurface. The key plug is enclosed by a split bearing sleeve 3l)extending the entire length thereof with the split ends 3l terminatingat opposite longitudinal sides of the milled surface 2l substantially inline with said flanges or abutment shoulders 29.

In the form of inventionv illustrated in Figure 5, the key plug isenclosed by a bearing cylinder 32 that has a series of longitudinallyextending spaced openings 33 therein disposed over the milled surface ofthe plug and of a diameter larger than the diameter of the tumbler pinreceiving holes 20 and with diametrically opposite sides of the openings33 substantially in line With said flanges or abutment shoulders 29. Thesplit sleeve 30 shown in Figurel `and the sleeve 32 shown in Figure 5are secured in position on the key plug by means of a set screw 34.

Froml the above detailed description of the invention, it is believedthat the construction and operation thereof will at once be apparent andwhile there are herein shown and described the preferred embodiments ofthe invention, it is nevertheless to be understood that minor changesmay be made therein without departing from the spirit and scope of theinvention as claimed.

I claim:

1. A lock including a cylinder, a plug rotatably mounted in saidcylinder and having a key slot, the cylinder and plug having registeringpin receiving holes, spring-pressed top driver mushroom-type pinsmounted in the cylinder holes, tumbler pinsmounted in the plug holes,and a pair of flanges extending longitudinally of the plug at theperiphery thereof in the zone of the tumbler pin holes for interlockingengagement With the top driver pins said flanges being spaced laterallyof the holes in the plug.l

2. A lock including a cylinder, a plug rotatably mounted in saidcylinder and having a key slot, the cylinder and plug having registeringpin receiving holes, spring-pressed top driver mushroom-type pinsmounted in the cylinder holes, tumbler pins mounted in the plug holes,the top surface of the plug having a longitudinally milled surfaceextending across the outer ends of the tumbler pin holes in the plugwith the side edges of the milled surface disposed laterally from saidholes at opposite sides thereof and providing longitudinal abutmentshoulders laterally of said holes for abutting engagement with the topdriver pins at points inwardly of the periphery of the plug.

3. A lock including a cylinder, a plug rotatably mounted in saidcylinder and having a key slot, the cylinder and plughaving registeringpin receiving holes, spring pressed top driver mushroom-type pinsmounted in the cylinder holes, tumbler pins mounted in the plug holes,the top surface of the plug having a longitudinally milled surfaceextending across the outer ends of the tumbler pin holes in the plugwith the side edges of the milled surface disposed laterally from saidholes at opposite sides thereof and providing longitudinally extendingside grooves laterally of the milled surface and laterally of thetumbler pin holes for reception of the mushroom heads of the top driverpins to prevent rotation of the key plug to bolt releasing position.

4. A lock including a cylinder, a plug rotatably mounted in saidcylinder and having a key slot, the cylinder and plug having registeringpin receiving holes, spring pressed top driver ,mushroom-type pinsmounted in the cylinder holes, tumbler pins mounted in the plug holes,the top surface of the plug having a longitudinally milled surfaceextending across the outer ends of the tumbler pin holes in the plugwith the side edges of the milled surface disposed laterally from saidholes at opposite sides thereof and an inwardly directed longitudinallyextending fiangeat each side of the milled surface spaced outwardly ofsaid milled surface and laterally of said holes and defining alongitudinally extending groove laterally of the tumbler pin holes forreception of the mushroom heads of the top driver pins to preventrotation of the key plug to bolt releasing position.

5. A lock as set forth in claim 1, characterized by a split bearingsleeve inclosing the key plug with the split ends of the sleeverespectively terminating at opposite sides of the milled surface andlaterally of said holes and in line with said flanges.

6. A lock as set forth in claim 2, characterized by a split bearing,sleeve inclosing the key plug with the split ends of the sleeverespectively terminating at opposite sides of the milled surface andlaterally of said holes and in line with said abutment shoulders.

7. A lock as set forth in claim 1, characterized by a bearing sleeveinclosing the keyplug and having aseries of openings therein registering

